From owner-cvs-all Sun Sep 22 20:28: 7 2002 Delivered-To: cvs-all@freebsd.org Received: by hub.freebsd.org (Postfix, from userid 931) id BD52737B401; Sun, 22 Sep 2002 20:28:03 -0700 (PDT) Date: Sun, 22 Sep 2002 20:28:03 -0700 From: Juli Mallett To: Alfred Perlstein Cc: Jeff Roberson , Greg 'groggy' Lehey , Jeff Roberson , cvs-committers@FreeBSD.org, cvs-all@FreeBSD.org Subject: Re: cvs commit: src/sys/kern kern_alq.c src/sys/sys alq.h Message-ID: <20020922202803.A95505@FreeBSD.org> References: <20020923003727.GM21093@wantadilla.lemis.com> <20020922211607.E43954-100000@mail.chesapeake.net> <20020923020717.GC6262@elvis.mu.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.2.5.1i In-Reply-To: <20020923020717.GC6262@elvis.mu.org>; from bright@mu.org on Sun, Sep 22, 2002 at 07:07:17PM -0700 Organisation: The FreeBSD Project X-Alternate-Addresses: , , , , X-Towel: Yes X-LiveJournal: flata, jmallett X-Negacore: Yes Sender: owner-cvs-all@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.ORG * De: Alfred Perlstein [ Data: 2002-09-22 ] [ Subjecte: Re: cvs commit: src/sys/kern kern_alq.c src/sys/sys alq.h ] > * Jeff Roberson [020922 18:28] wrote: > > On Mon, 23 Sep 2002, Greg 'groggy' Lehey wrote: > > > > > On Sunday, 22 September 2002 at 0:11:14 -0700, Jeff Roberson wrote: > > > > jeff 2002/09/22 00:11:14 PDT > > > > > > > > Added files: > > > > sys/kern kern_alq.c > > > > sys/sys alq.h > > > > Log: > > > > - Add an asynchronous fixed length record logging mechanism called > > > > ALQ (Asynch. Logging Queues). ALQ supports many seperate queues with > > > > different record and buffer sizes. It opens and logs to any vnode so > > > > it can be used with character devices as well as regular files. > > > > > > What's the purpose of this functionality? > > > > > > Greg > > > -- > > > See complete headers for address and phone numbers > > > > > > > Well, for now it's only used by ktr. I believe that it could be applied > > to other areas as well. In general I need it for recording long term > > events such as disk or network activity for post analysis. It could also > > be useful for diagnosing problems with VFS by logging all VOPs via ktr. > > > > It could also be used for logging binary kernel data w/o going through > > ktr. Any subsystem could create a queue and record it's actions over a > > long period. ktrace could be implemented on top of an ALQ, although this > > would be slightly more difficult since it does not use fixed length > > records. > > Have you thought of running it into a fifo with gzip waiting on the > other side? I guess that could sort of cause an infinite loop if > you were recording certain process/vnode interaction unless it was > batched up somehow. Add an ALQ mutex to a vnode, and check for recursion? -- Juli Mallett | FreeBSD: The Power To Serve Will break world for fulltime employment. | finger jmallett@FreeBSD.org http://people.FreeBSD.org/~jmallett/ | Support my FreeBSD hacking! To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe cvs-all" in the body of the message